Via kottke, we discovered the Free Universal Construction Kit, a set of 80 two-way adapters that allows kids to connect Legos and Tinkertoys together: “By allowing any piece to join to any other, the Kit encourages totally new forms of intercourse between otherwise closed systems—enabling radically hybrid constructive play, the creation of previously impossible designs, and ultimately, more creative opportunities for kids. As with other grassroots interoperability remedies, the Free Universal Construction Kit implements proprietary protocols in order to provide a public service unmet—or unmeetable—by corporate interests” (emphasis in original).